Atomic Force Microscopy Characterization of Protein Fibrils Formed by the Amyloidogenic Region of the Bacterial Protein MinE on Mica and a Supported Lipid Bilayer

Ya-Ling Chiang; Yuan-Chih Chang; I-Chen Chiang; Huey-Ming Mak; Ing-Shouh Hwang; Yu-Ling Shih

doi:10.1371/journal.pone.0142506

Atomic Force Microscopy Characterization of Protein Fibrils Formed by the Amyloidogenic Region of the Bacterial Protein MinE on Mica and a Supported Lipid Bilayer

PLoS One. 2015 Nov 12;10(11):e0142506. doi: 10.1371/journal.pone.0142506. eCollection 2015.

Authors

Ya-Ling Chiang^{1

2}, Yuan-Chih Chang³, I-Chen Chiang⁴, Huey-Ming Mak⁴, Ing-Shouh Hwang^{1

2}, Yu-Ling Shih^{4

5}

Affiliations

¹ Institute of Physics, Academia Sinica, Taipei, Taiwan.
² Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan.
³ Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan.
⁴ Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan.
⁵ Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan.

Abstract

Amyloid fibrils play a crucial role in many human diseases and are found to function in a range of physiological processes from bacteria to human. They have also been gaining importance in nanotechnology applications. Understanding the mechanisms behind amyloid formation can help develop strategies towards the prevention of fibrillation processes or create new technological applications. It is thus essential to observe the structures of amyloids and their self-assembly processes at the nanometer-scale resolution under physiological conditions. In this work, we used highly force-sensitive frequency-modulation atomic force microscopy (FM-AFM) to characterize the fibril structures formed by the N-terminal domain of a bacterial division protein MinE in solution. The approach enables us to investigate the fibril morphology and protofibril organization over time progression and in response to changes in ionic strength, molecular crowding, and upon association with different substrate surfaces. In addition to comparison of the fibril structure and behavior of MinE1-31 under varying conditions, the study also broadens our understanding of the versatile behavior of amyloid-substrate surface interactions.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aluminum Silicates / chemistry
Aluminum Silicates / metabolism*
Amyloid / chemistry
Amyloid / metabolism*
Amyloid / ultrastructure
Cell Cycle Proteins / chemistry
Cell Cycle Proteins / metabolism*
Escherichia coli Proteins / chemistry
Escherichia coli Proteins / metabolism*
Humans
Lipid Bilayers / chemistry
Lipid Bilayers / metabolism*
Microscopy, Atomic Force / methods*
Microscopy, Electron, Transmission
Molecular Dynamics Simulation
Peptide Fragments / chemistry
Peptide Fragments / metabolism
Protein Structure, Secondary
Protein Structure, Tertiary

Substances

Aluminum Silicates
Amyloid
Cell Cycle Proteins
Escherichia coli Proteins
Lipid Bilayers
MinE protein, E coli
Peptide Fragments
mica

Grants and funding

This work was funded by a career development award AS-98-CDA-L07 to YLS, and by the Thematic Research Program (AS-102-TP-A09) to YLS and ISH from Academia Sinica, Taiwan and by grants NSC 101-2311-B-001-006 to YLS, NSC 102-2112-M-001-024-MY3, MOST 103-2627-M-001-011, and MOST 104-2627-M-001-005 to ISH from Ministry of Science and Technology, Taiwan. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.